Purification of fluids with cation active resins



Patented May 13, 1947 PURIFICATION OF FLUInswI'rII oA'rIonAc'rIvI;Iussnvs- James R. Dudley, Cos Cob, Conn.,"asslgnor to AmericanCyanamid Company, Ne YorlgN. Y.,

a corporation of Maine No Drawing. ApplicationvMarch 30,1944,

sfll'ifll N0. 528,769

6 Claims. (01. 210+24) f This invention relates t3 the removal ofcations from fiuid media, to the exchange of cations in fluid media, andto the purification of fluid media.

An object of this invention is to provide a process for removing cationsfrom fluid media.

Another object of my invention is to purify fluid media, and moreparticularly aqueous media, containing undesired cations.

These and other objects are attained by contacting the fluid to betreated with a material obtained by reacting furfural with a mineralacid halide and resinifying to a water-insoluble form. The followingexamples in which the proportions are in parts by weight are given byway of illustration and not in limitation. The iuriural used is of 95%purity.

Example 1 A cylinder or other vessel is filled" with a granular cationactive material prepared in accordance with one or more of the examplesset forth below. Through this bed of resin a dilute acid solution, e. g.02-10% sulfuric acid, is passed and the resin is activated after whichit is washed with water to remove residual acid. This bed of resin isnow in the so-called hydrogen activated state and is suitable forremoving cations from fluid media such as water. 1

Water containing about 50 P. P. M. of total solids including about 37 P.P. M. of non-volatile solids is passed through the bed of cation activeresin. The pH of the water before treatment is about 6.6 and aftertreatment, about 3. Most of the cations are removed. The acidity of theefliuent may be removed by passing it through an anion active resin, andthe water may be still further purified by passing it through anotherbed of cation active material after which it may be aerated to removecarbon dioxide or further treated with additional beds of anion andcation active materials. I

If the water contains only bases, the efliuent will be substantiallyneutral and free of cations until the capacity of the bed of resin isapproached. If, however, as in the above example, the water containssalt, the eiiluent will be acidic and for most purposes it is desirableto pass the eiliuent through abed of anion active resin to remove theacid. In most purification processes,

particularly if the salt contentof thefiuidto be treated is high, itwill be necessary ordesirable to employ a plurality, oi cation active.beds with an anion active bed between each of the cation active beds,substantially as described. T"

- Example 2,; t

About'lO liters of an aqueous solution contain ing 50% of crude canesugar which is dark brown in color, quite turbid and has-a pH oil about-6.5 is heated to about C. The solution may be subjected to apreliminary filtration ,ifdesired and is then passed through a bed of acation active material prepared in accordance with my invention, forexample, the resin of Example 9. The pH of the eflluent from the cationactive material which lsfa very pale yellow isabout 3 thereby indicatingthat cations have been re: moved with consequent release of acid formingradicals such as chloride, sulfate, sulfite, etc.

The eflluent may-be passed through an anion active resin to remove theacid and other anions tremely high purity and brilliance characteristic"of high grade sugar. Furthermore, if molasses be produced as aby-product from this sugar, it

is a high quality product having a light color and a very low content ofsalts as impurities. Other aqueous solutions containing cations may bepurified-in the same general manner as described in the'precedingexamples. Furthermore, other fluid'mediai containing cations may bepurifiedin the'same general manner. The following examples illustratethe cation active materials which are suitable for use in mypurification process. as well as processes for prepar ing suchmaterials.

The sulfuryl chloride is dissolved in theacetic acid, and the solutioncooledin an ice bath. The

boiled for 4 hours. The water iuriural is then added slowly withstirring so that the temperature of the solution doesnot exceed 20 C.When the addition is complete the solution is black and upon standingovernight, a very soft black gel is formed. Alter standing for anadditional day the 'gel becomes firm and hard.

The gel is reduced to particles of small size which are covered withwater and allowed to stand overnight. The water is then drained of! andthe resin dried for 4 hours at 100 C. and evaluated. The final productexhibits a capacity for the absorption or exchange of cations from waterequivalent to about 8,000 grains of calcium carbonate per cubic foot ofresin and the density or the material is about 12.2 pounds per cubicfoot.

Example 4 Example 3 is repeated but instead of soaking the small-sizedparticles of the gel, they are suspended in water and the mixture boiledfor 4 hours. The water resin dried for 4 hours at 100 C. The finalproduct exhibits a capacity for the absorption or exchange of cationsfrom water equivalent to about 7,100 grains of calcium carbonate percubic foot of resinand the density of the material is about 10.5 poundsper cubic foot.

Example 5 Example 3 is repeated but instead of soaking the gel particlesin water overnight. dry steam is passed through the resin for 4 hours.After this treatment the resin is dried for 4 hours at 100 C. andthefinal product has a capacity tor the absorption of cations from waterequivalent to about 9,600 grains of calcium carbonate per cubic foot ofresin. The density oi the material is about 13.2 pounds per cubic foot.

Example 6 Suliuryl chloride 540 parts (4.0 mols) Glacial acetic acid 840parts Furiural 1010 parts (10.0 mols) As in Example 3 the sulfurylchloride is dissolved in the acetic acid, this solution is cooled in anice bath, and the Iurfural is then added slowly with stirring so thatthe temperature of the Example 7 The procedure of Example 6 is followedexcept that instead of soaking the gel particles overnight they aresuspended in water and the mixture is is then drained oil and the resindried for 4 hours at 100 C. The final product exhibits a tion of cationsfrom water equivalent to about 15,600 grains of calcium carbonate percubic foot of resin and the density of the material is about Afterevaluation the resin is redried for 17 hours at 145 C. to give a producthaving a capacity equivalent to about 12,900 grains of cal- 15.6 poundsper cubic foot.

is then drained of! and the a as in Example 5. The resin is thencapacity for the absorpcium carbonate per cubic foot of resin and adensity of 7.! pounds per cubic root.

Example 8 The procedure of Example 8 is followed except that instead orsoaking the gel particles overnight, dry steam is passed through theresin m 4 hours dried or 4 hours at 100 C. and the iinal product foundto have a capacity for the absorption or exchange of cations from waterequivalent to about 14,100 grains of calcium carbonate per cubic foot ofresin. The resin has a density or 18.0 pounds per cubic foot.

Example 9 Suliury1'chloride 540 parts (4.0 Glacial acetic acid 840 partsFuriural. 1212 parts (12.0 mole) 'i'chiimliuryi chloride is dissolved inthe acetic The iinal cured and hydrolyzed product has a capacity for theabsorption or exchange or cation's irom water equivalent to about 18,300grains of calcium carbonate per cubic foot of resin and a density oi18.2 pounds per cubic foot.

Example 10 The procedure of Example 9 is repeatedexceptthatinsteadoisoakingthe cured resinparticles overnight they boiledfor 4 hours. Following this the water is drained oil and the resinisdried ior 4 hours at 100' C. The final product exhibits a capacity forthe or exchange of "cations from water equivalent to about 18,100 grainsoi calcium carbonate per cubic foot of resin and has a density of 18.4pounds per cubic foot.

Example 11 Example 12 Example 9 is repeated except that the curing stepis omitted. The hard brittle gel particles are suspended in water andboiled for 4 hours. After draining oi! the water. the resin is dried for4 hours at 100 C. and evaluated. The final product has a capacity torthe absorption of cations irom water equivalent to about 10,800 grainsof calcium carbonate per cubic foot and a density of 23.2 pounds percubic foot.

mole) are suspended in water and r 7 Exampl 13' y A Example 9 isrepeated except that the gel is not cured but particles thereof insteadare treated by passing dry steam therethrou'gh for 4 hours as describedin Example 5, and the. resin is then dried for 4 hours at 100 C.

The final producthas a capacity for the exchange of'cations in waterequivalent to about 12,800 grains of calcium carbonate per cubic footand a density of the materialis about 21.7 pounds per cubic foot.

Example 14 I t Phosphorus oxychloride 77' parts (0.5 mol) Glacial aceticacid 105 parts Furi'ural 101 parts (1.0 mols) The phosphorus oxychlorideis dissolved in the acetic acid and the solution cooled to about 3 C.The furfural, cooled to about 5 C. is then added. The solution is blackand after standing overnight a soft brittle rubbery black gel is fomed.Upon warming up, an exothermic reaction occurs in which acetic acid andhydrochloric acid fumes are distilled from the material. Upon cooling avery hard brittle gel is obtained.

Small-sized particles of the gel are covered with water and allowed tostand for 4 hours. Steam is then bubbledinto the mixture for 4 hours,the water is drained off, and the resin is dried for 4 hours at 100 C.The final product has a capacity for the absorption of cations fromwater equivalent to about 16,100 grains of calcium carbonate per cubicfoot of resin and the density of the material is about 17.5 pounds percubic foot.

Example 15 Phosphorus oxychloride '77 parts (0.5 mol) Glacial aceticacid 105 parts Furfural 152 parts (1.5 mols) The procedure of Example 14is followed throughout. The brittle black gel, somewhat firmer than thatformed in Example 14, has a capacity for the absorption of cations fromwater equivalent to about 17,300 grains of calcium carbonate per cubicfoot of resin. The density of the material is about 19.6 pounds percubic foot.

The mineral acid halides are preferably resinifled with furfural alonealthough a minor portion of the furfural may be replaced by otheraldehydes, particularly formaldehyde, a polymer of formaldehyde or asubstance yielding formaldehyde. Other aldehydes which may be usedinclude acetaldehyde, butyraldehyde, heptaldehyde, crotonaldehyde,acrolein, benzaldehyde, etc.

The resins of the present invention may be cured by heating at atemperature ranging from room temperature to about 150 C. for fromseveral hours to a day.

My resinous materials may be used alone or in admixture with othercation-active materials. Furthermore, my resins may be applied beforegelation to a suitable carrier such as diatomaceous earth, clays,charcoal, etc. In this way, the active resin is spread on the surface ofa relatively inert material and this enables one to employ a smallerquantity of resin than otherwise to obtain the same active area.

The granular resinous condensation products of furfural and mineral acidhalides, and particularly those having a particle size less than 8 mesh,are useful in the removal of cations from fluid media, especiallyaqueous solutions. The

resins may be usediu the hydrogen-activated I form to remove cationsfrom solutions 01' bases.

My resinous cation-active materials may, also be employed as exchangematerials in accordance with the principles applied to the use of thenaturaland synthetic zeolites. Thus, the resin may be activated withasodium salt such as sodium chloride and upon contact with a solution containing calcium, magnesium or other cations, an; exchange of thelatterions for the sodium ions takes place.

The activating solutionsor regenerating solutions are dilute acidsolutions or dilute salt so.-,

than about 1 part of resinln 1,000 parts of water.

when passedthrough a bed of resin (after the first cycle comprising anactivation, exhaustion and reactivation of the resin) My process ofpurifying fluid media is applicable not only to water purification andto the purification of sugar solutions as illustrated in Examples 1 and2, but also to the removal of heavy metal cations from foods, beveragesand pharmaceutical products, to the removal of basic dyes from fluidmedia, to the removal of valuable cations from dilute solutions, e. 8..gold from sea water, chromium from chrome tanning liquors, silver fromphotographic baths, etc. Another important application of mypurification process is in the absorption or adsorption of gases such asammonia, amines as e. g., triethylamine, methylamine, etc., from fluidmedia either dissolved in a liquid or from vapors. Such vapors mayconsist almost entirely of the gas to be ab-' sorbed or they may containa relatively inert gas such as air, nitrogen, carbon dioxide, etc.

I claim:

1. A process of removing cations from fluid media which comprisestreating a. fluid containing cations with a granular water-insolublecomposition of matter having a particle size or less than about 8 meshand comprising the hydrolyzed product of reaction of a mixture includingfurfural and a mineral acid halide selected from the group consisting ofsulfuryl chloride and phosphorus oxychloride, and separating the fluidfrom the water-insoluble composition of matter.

2. A process of removing cations from fluid media which comprisestreating a fluid contain ing cations with a granular water-insolublecomposition of matter having a particle size of less than about 8 meshand comprising the hydrolyzed product of reaction of a mixture includingfurfural and sulfuryl chloride, and separating the fluid from thewater-insoluble composition of matter.

3. A process of removing cations from fluid media which comprisestreating a fluid containins cations with a granular water-insolublecomposition of matter having a particle size of less than about 8 meshand comprising the hydrolyzed product of reaction of 'amixture includingfurfural and phosphorus oxychloride, and separating the fluid from thewater-insoluble 'com Position of matter.

4. A process which comprises passingan aqueous fluid containing cationsthrough a bed of a granular material, said material having a par- 7ticlesilsotlessthanabouttmeshandeomprisin: the hydrolned reactionproduct 01' a mixture includinl Iuriunl anda mineral acid halide oi thegroup consistinc oi suliuryl chloride end phosphorus oxychloride. V

6. A process which comprises passing an aque ous fluid containingcations through a bed oi a ulor material, said material havin: apartiele size or less than about 8 mesh and comprisis 2,355,402

. 8 ing the hydrolyzed reaction product oi a mixture including iuriuraland phosphorus oxychloridc. JAMIE R. DUDLIY.

3mm (3E8 CITED The following references are of record in the me oi thispatent:

UNI'IID STATE PATH.

l Number Name Date 1,682,934 Richardson Sept. 4, 1928 1,940,388 woodswckDec. 19, 1933 2,251,234 Swain .July 29, 1941 2,285,750 Swain June 9,1042 Bussman Aug. 8, i944

